g1smd - 7:55 am on Mar 15, 2010 (gmt 0) [edited by: g1smd at 8:25 am (utc) on Mar 15, 2010]
One thing about searchengine bots. They don't 'follow' links or redirects.
A user of a browser clicks a link, the browser requests the URL, the server sends a redirect status code and URL to the browser, the browser requests that new URL, the server responds, and so on.
A bot scans a page and adds any URLs it finds in links to its 'to be crawled' database. Minutes, hours, or days later it requests those URLs one at a time. For each URL requested, it either stores a page of content into the database to be scanned later, or it receives back both a redirect code and new URL and stores that URL in its database to be crawled later. So, there's lots of additional work to tie a chain of redirects together and 'count' the number in any chain.
[edited by: g1smd at 8:25 am (utc) on Mar 15, 2010]